Adjustably supported platform

ABSTRACT

A PLATFORM IS MOUNTED ON A SUBSTANTIALLY VERTICAL SUPPORTING ROD. THE VERTICAL ROD IS MOUNTED FOR MOVEMENT BY THE OPERATOR TO VARIOUS POSITIONS WITHIN THE WORK AREA. THE PLATFORM EXTENDS PERPENDICULARLY FROM THE VERTICAL ROD AND IS JOURNALLED FOR ROTATION IN A HORIZONTAL PLANE. THE JOURNAL BETWEEN THE PLATFORM AND THE ROD IS FORMED BY A SLEEVE AND INDEXING TEETH ARE PROVIDED IN A CONCENTRIC RING AT THE BASE OF THE SLEEVE, WHICH ENGAGES A MATINGLY INDEXED CAP ON THE ROD. A VERTICAL COMPONENT OF THE WEIGHT OF THE PLATFORM HOLDS THE INDEXED PORTIONS IN ENGAGEMENT. TO ROTATE THE PLATFORM THE INDEXED PORTIONS MUST FIRST BE DISENGAGED BY LIFTING THE SLEEVE SO THAT THE SLEEVE SLIDES UPWARDLY ALONG THE ROD. VARIOUS EMBODIMENTS ENCOMPASS DIFFERENT SUPPORTS FOR THE VERTICAL ROD AND INCLUDE A PENDANT SUPPORT FROM AN OVERHEAD TRACK, AS WELL AS A FLOOR SUPPORT INCLUDING A CASTER AND A GENERALLY HORIZONTAL GUIDE RAIL. ANOTHER EMBODIMENT INCLUDES A RIM JOURNALLED FOR ROTATION ABOUT THE CYLINDRICAL BASE OF A CHAIR AND AN INDEXING DETENT TO PREVENT ROTATION OF THE RIM AFTER THE DESIRED POSITION OF THE VERTICAL SUPPORTING ROD HAS BEEN OBTAINED.

Oct. 26, 1971 CAGLE 3,615,153

ADJUSTABLY SUPPORTED PLATFORM Filed April 22, 1970 2 Sheets-Sheet 1 I AM' II II 11 11/11/11 11 II II II 1/ E. E. CAGLE ADJUSTABLY SUPPORTED PLATFORM Get. 26, 1911 2 Sheets-Sheet 2 Filed April 22, 1970 NT/BGO mvnm m. EUNICE E. CAGLE Patented Oct. 26, 1971 3,615,153 ADJUSTABLY SUPPORTED PLATFORM Eunice E. Cagle, Rte. 4, Hancevilie, Aia. 35077 Filed Apr. 22, 1970, Ser. No. 30,652 Int. Cl. A47f 5/08 U.S. Cl. 211-113 9 Claims ABSTRACT OF THE DESCLOSURE A platform is mounted on a substantially vertical supporting rod. The vertical rod is mounted for movement by the operator to various positions within the work area. The platform extends perpendicularly from the vertical rod and is journalled for rotation in a horizontal plane. The journal between the platform and the rod is formed by a sleeve and indexing teeth are provided in a concentric ring at the base of the sleeve, which engages a matingly indexed cap on the rod. A vertical component of the weight of the platform holds the indexed portions in engagement. To rotate the platform the indexed portions must first be disengaged by lifting the sleeve so that the sleeve slides upwardly along the rod. Various embodiments encompass different supports for the vertical rod and include a pendant support from an overhead track, as well as a floor support including a caster and a generally horizontal guide rail. Another embodiment includes a rim journalled for rotation about the cylindrical base of a chair and an indexing detent to prevent rotation of the rim after the desired position of the vertical supporting rod has been obtained.

Platform supports adjustable in both vertical and horizontal planes with indexing means for preventing movement of the platform.

Beauticians have long felt the need for adequate work table storage surface adjustably positioned around the operating chair so that their necessary work implements may be easily reached and are constantly within the beauticians grasp as he is moving about the patron. This need for suitable implement supporting surfaces is extremely acute due to the fact that the beautician must work in a limited space area and walk about the operating chair. Any equipment supporting surfaces must therefore be not only within the beauticians grasp, but must also be movable so that it will not interfere with the beautician as he is walking from one side of the patron to the other.

In similar professional fields, such as dentistry or medicine, analogous circumstances arise. Thus, the dentist who is constantly standing on his feet and moving from one side of the patient to the other also needs a movable equipment supporting surface which may be moved out of his path of travel during his operating procedures, yet will maintain the equipment easily within his grasp. Such equipment supporting surfaces are highly desirable in these occupations because the worker is constantly on his feet and the less movement required of him, the less strenuous the days activity will be.

In the field of dentistry a standard dentists equipment tray is quite familiar. This tray has certain inherent disadvantages however. Most trays are not vertically adjustable and therefore they are moved only horizontally out of the dentists way or line of vision. Furthermore, the dentists work tray is not adequately adjustable even along a horizontal plane. Most dentists trays are rotatable in a horizontal plane and often since there is no indexing stop to lock the tray in a fixed position, once such position has been found, the tray will often inadvertently rotate and the dentist will lose track of the equipment or will not find the equipment readily within his grasp in the position in which it was last seen.

In the field of beauty parlor operations, the necessity for suitable movable equipment carrying trays or surfaces is even more acute because the beautician does not normally have a fixed equipment stand from which a movable work table or storage surface may be mounted. Because a beautician, unlike a dentist, must move in all directions about the patron, that is, must move not only to the left but the right side of the patrons head, a fixed or rigid stand projecting from one side of the beauticians chair will limit the beauticians activity and thus impede his normal movements. Thus, there are presently no equipment carrying trays in use in conjunction with beauty parlor operations because none have been found acceptable to the particular use of. beauticians who must move constantly about the operating chair.

A further disadvantage encountered with some of the prior tray supporting equipment was the fact that either the trays themselves were not movable about the tray support or, if the trays were movable, there was no easily actuated locking device to hold the tray in one position so that the operator would readily know where each separate implement placed on the tray was located.

It is an object of the present invention to provide an adjustably supported platform of the general character described which is so constructed that it is not subject to any of the foregoing disadvantages.

More specifically it is an object of the present invention to provide an adjustably supported platform of the general character described which may be operated with great facility and which greatly speeds the normal functions of an operator by placing needed implements at the operators fingertips, yet can be manufactured by mass production methods at a cost appreciably lower than prior devices designed to serve the same function.

A further object of the present invention is to provide an adjustably supported platform of the general character described which includes a vertical supporting rod and a platform rotatably journalled on said rod for movement in a horizontal plane.

Yet another object of the present invention is to provide an adjustably supported platform of the general character described which includes a substantially vertical support rod and means for moving the support rod in a fixed path along a designated work area.

A still further object of the present invention is to provide an adjustably supported platform of the general character described which includes a work implement supporting surface and means to rotate the surface in a generally horizontal plane along with indexing means to hold the surface in a fixed position.

Another object of the present invention is to provide an adjustably supported platform of the general character described which includes a pendant vertical rod for supporting a tray and a ceiling mounted supporting track, portions of which are at different elevations above the floor supporting surface, so that the height of the tray may be adjustably varied by supporting the vertical rod from different positions along the track.

Yet another object of the present invention is to provide an adjustably supported platform of the general character described which includes a vertical supporting rod and guide means concentrically mounted about an operating chair so that the rod may be moved to various positions around the chair as the operator moves about a patron.

A further object of the present invention is to provide an adjustably supported platform of the general character described Which includes a supporting rod which projects upwardly from a cylindrical base of an operating chair and which includes a collar journalled for rotation about the chair base and supporting the rod along with indexing means for fixing. the position of the rod with respect to the operating chair.

3 Other objects of the invention in part will be obvious and in part will be pointed out hereinafter.

The invention accordingly consists in the features of construction, combination of elements and arrangements.

of parts which will be exemplified in the adjustably supported platform hereinafter described, and of which the scope of application will be indicated in the appended claims.

In the accompanying drawings, in which are shown some of the various possible embodiments of the invention,

FIG. 1 is an elevation view illustrating the application of one embodiment of the invention in a beauticians work area with the embodiment including an overhead supporting track from which a vertical rod is suspended and with a platform rotatably journalled adjacent the lower end of the rod.

FIG. 2 is an enlarged fragmentary sectional view through the overhead track, the same being taken substantially along the line 2-2 of FIG. 1 and illustrating the manner in which the vertical rod engages various notches along the overhead frame to vary the position and elevation of the rod.

FIG. 3 is a sectional view taken along the line 3-3 of FIG. 1 and illustrating the top surface of a platform which carries various implements used by a beautician; additionally shown in broken lines is a possible alternate position of the platform after the same has been rotated approximately 180 about the vertical shaft.

FIG. 4 is an enlarged fragmentary sectional view taken substantially along the line 44 of FIG. 3 and showing various implements on the platform along with a tissue box carried in a tray additionally formed in the platform.

FIG. 5 is a fragmentary sectional view taken substantially along the line 55 of FIG. 4 and illustrating a sleeve formed in the platform through which the vertical shaft is journalled; further illustrated is an end cap secured to the base of the vertical shaft to provide indexing means to hold the platform against free rotation about the vertical shaft.

FIG. 6 is a fragmentary auxiliary view taken substantially along the line 6-6 of FIG. 5 and illustrating the undersurface of the platform including various supporting ribs along with the bottom of the cap secured at the end of the vertical shaft; additionally shown in the cap is a recessed socket which facilitates the tightening thereof.

FIG. 7 is an enlarged fragmentary auxiliary view taken substantially along line 7-7 of FIG. 5 and illustrating matingly ridged surfaces at the bottom of the sleeve and the cap which provide indexing means for restraining the free rotation of the platform about the vertical rod.

FIG. 8 is a further elevational view of an alternate embodiment of the invention also adapted for use in a beauticians work area and mounted for movement in a concentric path about the base of a chair.

FIG. 9 is a sectional view through the supporting rod and the base of the chair, the same being taken substantially along the line 9-9 of FIG. 8 and illustrates a track extending concentrically about the chair and a shoe which rides along the track.

FIG. 10 is an enlarged fragmentary sectional view taken substantially along the line 1010 of FIG. 8 and illustrating the engagement between a sleeve on the platform and an indexing collar extending from the rod.

FIG. 11 is an auxiliary view taken substantially along the line 1111 of FIG. 8 and illustrating the shoe which is secured to the end of the rod.

FIG. 12 is a further elevational view of still another embodiment of the invention adapted for movement in a concentric path about the base of a chair.

FIG. 13 is a sectional view through the base of the chair, the same being taken substantially along the line 13-13 of FIG. 12 and illustrating a spoked wheel journalled for rotation about a cylindrical portion of the chair base and to which the supporting rod is mounted.

FIG. 14 is an enlarged fragmentary sectional view taken substantially along the line 14-44 of FIG. 13 and showing a detent secured to the lower end of the supporting rod and engaging a notch in the base of the'chair to lock the device.

FIG. 15 is a fragmentary sectional view taken substantially along the line 15-15 of FIG. 14 and illustrating the manner in which the detent engages a selected notch.

Referring now in detail to the drawings, reference numeral 10 denotes an adjustably supported platform device 10 constructed in accordance with and embodying the invention. The device 10 includes a one-piece molded platform 12 journalled for rotation about a substantially vertical axis so that it may be rotated to render readily accessible any implements or instruments which are carried therein. The platform 12 is preferably molded from any suitable synthetic plastic such as polyethylene, polypropylene, polystyrene, styrene-acrylonitrile copolymer, etc.

The platform 12 includes an upper and a lower level and is of generally symmetrical shape. The upper and lower levels are interconnected by a tubular sleeve 14 from the upper end of which a substantially horizontal counter 16 projects radially. The upper surface of the counter 16 includes recessed portions 18 forming trays. The trays formed of the recessed portion 18 may be used to carry any suitable implements which should be readily accessible to the user. As illustrated in the drawings with the device 10 being used by a beautician, the recessed portions 18 carry a tissue box 20 and a bin 22 within which hairpins are carried.

Two buckets 24 are formed in the platform and are spaced from the counter 16 on opposite sides of the longitudinal axis thereof. The buckets 24 are of generally truncated conical shape and further include an open top and a plurality of upstanding ribs 6 which serve t6 rigidify the bucket structure. Spacing flanges 28 project from the sides of the counter 16 and are integrally connected to the upper ends of selected ribs 26 which are adjacent the edges of the counter 16. The buckets 24 are supported from the bottoms thereof by a rib network which includes a circular rib 30 which is unitarily formed and concentric with the bottom of each bucket 24. Each circular rib 30 is spaced from the other rib 30 by a spacer arm 32 (see FIG. 6) which extends radially outwardly from the periphery of each circular rib. The spacer arm 32 is in turn connected to the sleeve 14 by a compression strut 34 which extends radially from the sleeve 14 at the base thereof. It should be noted in passing that the longitudinal axis of the counter 16 and the longitudinal axis of the compression strut lie within the same vertical plane and are parallel to each other.

Although the structure of the platform 12 has been described as being fabricated of molded synthetic plastic material in one piece construction, it will be appreciated that the components of the platform may be separately formed, e.g. the buckets 24 may be formed of a separate pail which may be nestably removeably received between the ribs 26.

From an observation of FIGS. 2 and 4 wherein typical beauticians implements are shown within the buckets, bins and other implement carrying surfaces of the platform 12, that the buckets 24 are suitable for carrying hair rollers. Optionally, even larger items or bulkier items may be carried in the buckets such as aerosol hairspray bombs, etc. Another bucket 24 is illustrated as carrying a plurality of bobby pins. The application of these implements is merely typical and various other implements may be carried for use by beauticians, and if the device 10 is to be used in other applications by other persons such as factory workers, dentists or barbers, other implements would be carried in the various compartments.

Various mounting arrangements are contemplated in this invention for supporting the platform 12 so that it may not only rotate but may also be moved about the work area. Generally, and as specifically illustrated in the embodiment of FIGS. 1-7, the platform 12 is supported by a substantially vertical rod 36 which is suspended from a suitable track 38 secured to the ceiling of the work area. The rod 36 is substantially cylindrical and the lower portion thereof is received within a bore extending through the sleeve 14. To captively retain the platform 12 on the rod 36. a cap 40 is secured to the base of the rod 36 and the head of the cap 40 is of a diameter greater than that of the bore extending through the sleeve 14 so that the platform 12 is carried by the rod 36 with the base of sleeve 14 in abutting contact with the head of the cap 40. The cap 40 includes a threaded shank 41 which extends into a matingly threaded bore at the end of the rod 36 to secure the cap to the rod 36. A socket 43 is formed on the cap to facilitate securement of the cap to the rod, and such socket is engaged by a typical turning implement, e.g. an Allen wrench.

The weight of the platform and any implements thereon bear on the rod as a cantilever support. In fact, the stresses applied to the portion of the counter 16 adjacent the sleeve 14 are tensile stresses while the stresses applied to the compressive strut 34 are, naturally, compressive stresses.

The clearance between the bore extending through the sleeve 14 and the cylindrical surface of the rod 36 nestably received therein is such that the sleeve and hence the platform are free to rotate about the rod 36. Such rotation facilitates the use of the platform device and a typical alternate position of the platform is illustrated in the broken lines of FIG. 2. In this position the platform has been rotated approximately 180 and such position may be achieved by rotation either in a clockwise or a counter-clockwise direction as indicated by the heavy arrows of FIG. 2.

The device 10 contemplates an indexing mechanism to prevent inadvertent rotational movement of the platform once a desired position has been achieved. For this purpose, the base of the sleeve 14 includes a serrated indexing surface 42 (see FIG. 7) and the abutting corresponding surface of the head of the cap 40 includes a mating serrated surface. Thus, in its normal position the serrated ridges and grooves on the surface 42 will mate with the serrations on the cap 40. Such engagement is assured by the components of the weight of the platform and any instruments carried thereon which act downwardly along the axis of the sleeve.

To rotate the platform to an alternate position, it is only necessary to lift the platform, i.e. the sleeve 14, to a position wherein the serrations are not in engagement. Such position is illustrated in FIG. 7. Thereafter, the sleeve 14 may be rotated as indicated in the heavy arrow of FIG. 7.

Various means for supporting and moving the rod 36 in the work area. In the preferred embodiment the upper end of the rod 36 includes an enlarged boss 44 with a rectangular slot 46 extending therethrough. The track 38, which is mounted on the ceiling of the work area, extends through the slot 46 and the device 10 is supported above the work area thereby. It should be noted that the thickness of the track 38 is slightly less than the width of the slot 46 so that the rod 36 may be slid along any selected portion of the track 38.

In order to fix the position of the device 10 along the work area, the track 38 is provided with a plurality of downwardly extending notches 48 (see FIG. 1). The width of each notch 48 is greater than the thickness of the boss 44 so that when the rod 36 is aligned with a notch 48 the weight of the device 10 is suflicient to cause the upper end of the boss 44 to engage the notch 48 and slide therein to abut the base of the notch 48. Additionally it can be seen from FIG. 1 that the elevation of the device may be appropriately adjusted by moving the rod 36 to different notches because the track 38 is of curved configuration wherein various notches are spaced from the supporting ceiling varying distance.

It will be appreciated that the precise configuration of track 38 is a matter of specific work area consideration and therefore the most expedient track consideration should be determined only after considering the work area and movement of the individual worker. Therefore, it is conceivable to alternately shape the track 38 in a path which is concentric with the base of the chair shown in the illustration of FIG. 1 and still include a plurality of notches at dilferent elevations.

An alternate embodiment of the invention is illustrated in FIGS. 8-11. In this embodiment the construction of a platform 12a is identical to that of the previously described platform 12. This embodiment differs however from the embodiment previously described because the platform 12a is supported and moved about the work area in a different manner.

In this embodiment the platform 12a is journalled for rotation about a substantially vertical supporting rod 36a which extends upwardly. A serrated surface 42a at the base of a sleeve 14a of the platform 12a engages mating serrations formed on a collar 50 which projects radially from the rod 36a. The mating serrations forming an indexing means to prevent inadvertent rotation of the platform 12a about the rod 36a. The serrations of the mating surfaces are disengaged by lifting the platform 12a as in an identical manner to that previously described. Thus, the collar 50 serves the same function as the cap 40 in the preferred embodiment.

To prevent the platform 12a from completely disengaging the rod 36a, a cap 52 is provided at the upper end of the rod 36a. The cap 52 includes an enlarged head and a threaded shank which is engaged and received in a mat ingly threaded bore of the rod 36a. It should be noted that clearance is provided between the upper end of the collar 14a and the head of the cap 52 so that the platform 12a may be lifted a sufficient distance along the rod 36a so as to clear the engaged serrations whereupon the platform 12a may be rotated.

This embodiment differs from the embodiment previously disclosed in another aspect, to wit: the fact that the rod 36a is supported from the floor of the work area and a guide rail 48a is also supported from the floor. A shoe 54 is positioned at the lower end of the rod. The shoe 54 includes a base 56 and two substantially parallel depending legs 58. A caster 60 is journalled for rotation between the legs 58 the outer circumference of which extends beyond the tips of the legs 58 to contact the floor. Thus the fioor surface supports the weight of the rod 36a as well as the platform and any implements carried thereon.

It should be noted that the track 48a is shaped to con centrically circumscribe a major area around the beauticians work chair. The thickness of the track 48a is uniform throughout and the longitudinal axis of the shoe 54 is of a curved shape which is of the same diameter as the C-shaped track 48a (see FIG. 9). The track 48a extends around a portion of the chair and is maintained at an elevation above the floor supporting surface and parallel thereto. To support the track 48a above the floor surface, downwardly extending legs 62 are provided at the terminal ends of the track 48a.

A further embodiment of the invention is illustrated in FIGS. 12-15. In this embodiment, a platform 12b is identical in construction to the previous platform and the platform is mounted for rotation about a generally vertical portion of a rod 36b. The vertical portion of the rod 36b is, in fact, identical to the corresponding portion of the rod 36a. Thereafter, this embodiment differ in construc tion from the previous embodiment disclosed.

The embodiment hereinafter described includes an alternate arrangement for supporting the rod 36b so that the rod is mounted for rotation about a cylindrical base of the operators chair.

Referring now to FIG. 1 it will be observed that the upper portion of the rod 36b is vertically oriented and extends downwardly from the platform 12b to a point 62 from which it bends toward the base of the operators chair. The rod 36 terminates at a sleeve 64 which extends in a direction substantially perpendicular to the longitudinal axis of the rod 36b.

A rim 66 of spoked wheel configuraion (to be later described) extends through a bore in the sleeve 64. The rim 66 is of circular cross-section and the bore extending through the sleeve 64 is of a shape conforming to the rim 66. Extending inwardly from the rim 66 are a plurality of spokes 68. The spokes 68 terminate at a collar 70, which is in abutting contact with a cylindrical portion of the operators chair adjacent the base thereof.

The collar 70 is journalled for rotation about the cylindrical portion of the operators chair and is secured against vertical movement between parallel flanges 72 and 74 which form a track within which the collar 70 is seated. The flanges 72, 74 are secured to the cylindrical portion of the operators chair through mounting bolts (see FIG. 15).

The engagement between the sleeve 64 and the rim 66 is such that the sleeve 64 may rotate about the rim 66 in a plane perpendicular to the plane of the rim 66 and passing through the center of said rim. Translational movement of the collar along the length of the rim 66 is prevented by C-clips 76 which are mounted on the rim 66 in grooves therein which grooves are spaced apart a distance slightly greater than the length of the sleeve 64. Thus, the position of the platform and the rod 36b may be changed with respect to the operators chair by rotating the collar 70 about the cylindrical portion of the operators chair. Such rotation may be effected through the use of a force applied to the rod 36 in a direction tangential to the rim 66.

Attention is now directed to FIG. 15 wherein it will be observed that a plurality of notches 78 are provided on the undersurface of the lower flange 74. The notches 78 are evenly spaced from one another and provide indexing means for holding the rim 66 in a preselected position and preventing the same from moving without releasing a detent mechanism. A detent 80 projects from the sleeve 64 and beneath the undersurface of the flange 74. The tip 82 of the detent 80 normally rests within a selected notch 78 and is held therein by a moment created by the weight of the platform with its contents and the rod 36b acting about a pivot which is in fact the portion of the rim 66 within the sleeve 64. The moment is counterbalanced by the tip 82 of the detent 80 resting against a selected notch 78. To disengage the detent from a selected notch and thus free the indexing mechanism so that the position of the rod 36b and hence the platform 12b may be moved, the rod 36b is forced in a counterclockwise (as viewed in FIG. 12) direction to a position indicated in the broken lines in FIGS. 12 14, 15. In such position, the tip 82 of the detent 80 is not in engagement with the notch 78 so that the rotation of the rim 66 and collar 70 as well as the rod 36b may be accomplished.

Thus it will be seen that there is provided an adjustably mounted platform which achieves the various objects of the invention and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the present invention and as various changes might be made in the embodiment above set forth it is to be understood that all matter herein described or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. An adjustably mounted implement carrying device for use in a work area of limited space, said device comprising a platform, means forming a bore in said platform, a platform supporting rod, said rod having a sub stantially cylindrical vertical portion, the vertical portion of the rod being journalled for rotation in the bore, re leasable indexing means for locking the platform in a fixed position with respect to the rod, said indexing means comprising cooperating surfaces on the platform and the rod, said cooperating surfaces including a serrated sur face of annular configuration and a member engageable with the serrated surface, and means for moving the platform supporting rod within the work area, said means for moving the rod within the work area includes a track, the track being secured to a ceiling surface above the work area, portions of the track being spaced from the ceiling surface, means forming a slot through a portion of the rod adjacent the upper end thereof, the track extending through the slot With the rod thereby being slidable along the track and supporting the device in a pendant position.

2. A device constructed in accordance with claim 1, wherein the platform is provided with a sleeve, the bore being formed in the sleeve, the clearance between the cylindrical portion of the rod and the bore being sufficient to permit the platform to freely slide along the vertical portion of the rod, one of the cooperating surfaces being formed at the lower end of the bore, a vertical component of the weight of the platform exerting a downward force on the sleeve to thereby hold the cooperating surfaces of the indexing means in engagement, the cooperating surfaces of the indexing means being released from engagement by manually sliding the sleeve upwardly, whereby the position of the platform with respect to the rod may be selectively varied by rotating the platform about the rod.

3. A device constructed in accordance with claim 2, wherein the sleeve is positioned along the longitudinal axis of the platform and at one end thereof, whereby the platform is supported from the rod and bears the weight of any implements carried thereon in the manner of a cantilever support.

4. A device constructed in accordance with claim 1, wherein means forming a plurality of notches along the upper surface of the track are provided, the notches being spaced from one another, the width of each notch being greater than the thickness of the rod at the upper end thereof, whereby the upper end of the rod may be selectively seated within any one of the notches to hold the rod in a fixed position along the track.

5. A device constructed in accordance with claim 1, means positioning the track above the floor surface of the work area, the platform being positioned adjacent the upper end of the rod, and the lower end of the rod including means for slidably engaging the track whereby the device may be moved in a guided path within the work area.

6. A device constructed in accordance with claim 5, wherein means are provided for maintaining the lower edge of the track above the floor surface of the work area, the means for slidably engaging the track includes a shoe having a base and substantially parallel legs, the track being positioned between the legs, and a caster, the caster being positioned between the legs adjacent the tips thereof and in rolling engagement with the floor supporting surface.

7. A device constructed in accordance with claim 1, wherein the platform is positioned adjacent the upper end of the rod, the means for moving the rod within the work area include an annular collar, the collar engaging a substantially cylindrical portion of a chair positioned within the work area, a rim, the rim having a circular transverse cross-section and being concentrically positioned about the collar, spoke means interconnecting the collar and the rim, the lower end of the rod being connected to the rim, whereby the rod may be moved in a path about the operators chair and within the work area.

8. A device constructed in accordance with claim 7, wherein means are provided for locking the rod in a selected position within the work area, a sleeve, the sleeve being secured to the rod at the lower end thereof, the longitudinal axis of the sleeve being substantially perpendicular to the longitudinal axis of the rod, means forming a bore through the sleeve, the last named bore being of a diameter slightly larger than the transverse cross-section diameter of the rim, a portion of the rim being positioned within the last named bore and the rod being journalled for rotation about the rim, the means for locking the rod including a detent, the detent projecting from the rod adjacent the lower end thereof, and a cooperating notched surface, said notched surface circumferentially positioned about the cylindrical portion of the chair, the detent being engaged in a selected notch of the notched surface when the rod is in an idle position, the rod being urged toward said idle position by a movement created by weight of the platform and any implements carried thereon, the detent being disengaged from the selected notch by manually pivoting the rod about the rim in a direction opposite the movement,

References Cited UNITED STATES PATENTS 495,409 4/1893 Fry 211-115 2,430,606 11/1947 Franz 15114 2,830,707 4/1958 Schmidt 211113 2,957,672 10/1960 Logan 211113 X 3,330,594 7/1967 Cadle 287-14 X 3,411,735 11/1968 Hurd 2l1--113 X NILE C. BYERS, In, Primary Examiner 

